Hi, I have a new ring gear with 40 teeth. and I have a ruxtell and a rocky mountain over and under drive line tranny. I live at the base of an 8500 foot mountain range and have flat lands below me. So with both of my units I should have plenty of gears. I think I want 3.33 gears in the rear axle. Will a 12 tooth pinion gear fit my 40 tooth crown gear? Thanks, Scott
I think you need a special 40 tooth ring gear that is recessed on the rear side for the 12 and 13 tooth pinions. Ruckstell had such gears back in the day, but nowadays they're reproduced by Chaffins:
So is it the same problem with a 39 tooth ring gear?
I can recess the ring gear if thats the only problem. Thanks, Scott
I did read the message Roger posted. Good info. Can anyone tell me the depth of the recess on the 40 tooth gear? Thanks, Scott
I plan to try this so I'm quite interested in what you learn. One thought I've had is to "play" with the thrust washer thicknesses if I need to. It may ultimately mean "tweaking " the axle lengths, but as I usually end up making my own axle shafts, then not a big problem. Machining the back side of the crown gear might be a problem as I suspect it may be case hardened. Anyway all the best and please let us know what you learn
Les, I cut case hardened parts all the time. You need a stout lathe and tooling and there is a trick as to cutting hard parts. Its in the way you sharpen your insert.
I just need to know the depth of the recess. Scott
Care to share?
The only 40 tooth ring gear I have is a Ruckstell one, setting the depth gauge on my mill, it has .267" recess.
Thanks Frank, Thats the number I needed. Iam still washing up parts on this project but will post when its done, Scott
Scott, I have a 39 tooth ring gear mated to a 12 tooth pinion to give a 3.25:1 ratio. I had no problems setting up this combination in my Ruckstell. As Les says, I did have to play with the thrust washer thicknesses, but i always do that as a matter of course. If you machine them to different thicknesses it gives you more to play with.
Hope this helps.
Allan from down under.